1. Media Gateway Figure 8-1 Comparing PSTN and VoIP voice call setup

2. Figure 8-2 Relationship Between Signaling and Media Flow IP Phone – Calling party IP Media Gateway IP Phone – Called party Call setup Signaling Media Flow 80008001

3. Figure 8-3 Components of a Multimedia Communication Service H.323 Terminal H.323 MCU H.323 Gatekeeper H.323 Gateway H.323 Terminal IP Network PSTN ISDN

4. Figure 8-4 Gatekeeper IP Phones IP Media Gateway Voice Router IP IP WAN Media Gateway Gatekeeper IP Phones

5. Figure 8-5 H.323 Zones IP Phones IP Media Gateway Router IP IP WAN Gatekeeper IP Phones MCU Router

6. Figure 8-6 Interdomain routing AS 300 AS 200 AS 100 BGP protocol running here connecting the three AS (Autonomous Systems) together

7. Figure 8-7 Signaling separate from VoIP conversation Real time Transport Protocol VoIP Conversation UDP Call setup signaling 1. Off hook 2. Send Dial tone 3. Dial number 6 Receive IP 4. is phone on hook? Yes 5.Give caller ip address 7. set up UDP port 8. Ring signal Called party Calling party Signaling uses TCP/IP Conversation uses UDP Media Gateway

8. Chapter 8 Figures [FIG]Figure 8-1 Comparing PSTN and VoIP voice call setup [FIG]Figure 8-2 Relationship between signaling and media flow [FIG]Figure 8-3 Components of a multimedia communication service [FIG]Figure 8-4 Gatekeeper [FIG]Figure 8-5 H.323 Zones [FIG]Figure 8-6 Interdomain routing [FIG]Figure 8-7 Signaling separate from VoIP converstion